Field of the Invention
The present invention concerns a blowing nozzle for a highly pressurized gaseous fluid comprising at least two narrow exhaust passages having a width insignificantly larger than the size of particles, occurring in said fluid.
Description of the Prior Art
Blowing nozzles are used for various industrial purposes, e.g. to blow away cuttings from a boring and other debris from a workpiece, to cool during welding or other kind of heat generating work, as exhausts from pneumatic machines, or for drying of paint.
A major problem with these devices is the risk of the noise level becoming hazardous, when a high blowing power is needed. Noise levels around 113 dB (A) are not uncommon for blowing nozzles with high output.
Noise reducing blowing nozzles are known, e.g. from Swedish patent application No. SE 7806883-0, which has several small circular passages. These small passages must be drilled with a very high degree of precision, in order to achieve the desired noise reducing effect. Because of the necessity for a high degree of precision these nozzles are comparatively expensive to manufacture. At the same time the blowing force possible with one of these nozzles is limited, which means that several nozzles must be mounted in parallel in order to reach a desired large blowing force. This means that these noise-reducing blowing nozzles in many cases are a very expensive solution to the noise problem.